Convert i960 COFF to use COFF backend linker.

	Convert i960 COFF to use COFF backend linker.
	* coff-i960.c (coff_i960_relocate): Use a coff_section_data
	structure to store the symbol being used.
	(coff_i960_start_final_link): New static function.
	(coff_i960_relocate_section): New static function.
	(coff_i960_adjust_symndx): New static function.
	(coff_start_final_link): Define.
	(coff_relocate_section): Define.
	(coff_adjust_symndx): Define.
	* coffcode.h (bfd_coff_backend_data): Add new callback function
	_bfd_coff_start_final_link.
	(bfd_coff_start_final_link): Define.
	(coff_start_final_link): Define if not defined.
	(bfd_coff_std_swap_table): Add coff_start_final_link.
	* cofflink.c (_bfd_coff_internal_syment_name): Make globally
	visible.
	(_bfd_coff_final_link): Call bfd_coff_start_final_link if the
	function callback is not NULL.
	* libcoff-in.h (struct coff_section_tdata): Add tdata field.
	(_bfd_coff_internal_syment_name): Declare.
	* libcoff.h: Rebuild.
	* configure.in (icoff_big_vec): Add cofflink.o.
	(icoff_little_vec): Likewise.
	* configure: Rebuild.